用一个循环建议逻辑来连接没有strcat的两个字符串

Question

我为concatenate two strings without using strcat编写了一个程序，为初学者使用两个while循环。需要你的建议用一个循环编码。请分享您的逻辑，谢谢

Answer 1

char first[1000];
char second[2000];
char result[4000];

void concat(char *first, char *second, char *result){
  int str_selector = 0;
  int i = 0, result_pos = 0;
  char *current_str = first;
  while(1){
    if(str_selector == 1 && current_str[i] == '\0'){
      result[result_pos] = '\0';
      break;
    }

    if(str_selector == 0)
      current_str = first;
    else
      current_str = second;

    if(current_str[i] != '\0'){
      result[result_pos] = current_str[i];
      result_pos++;
      i++;
    }
    else{
      i = 0;
      str_selector = 1;
    }
  }
}